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    <title>Document</title>
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    <h3>biaoti 1</h3>
    <h3>biaoti 2</h3>
    <h3>biaoti 3</h3>
    <script>
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            var result=Array.from(arguments);
            result.push(40);
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        add(10, 20, 30);

        let titles= document.querySelectorAll('h3');
        console.log(titles);

        var user={
            "0":"iwen",
            "1":19,
            "2":"男",
            length:3
        }

        console.log(user["0"]);

        console.log(Array.of(10,20,30));

    </script>
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